ShibbolethLogin: made name and surname optional

classes/login/ShibbolethLogin.php

@@ -22,8 +22,12 @@ class ShibbolethLogin extends LoginHandler {
 
             return $this->onIdentityDataReceived($eppn, function($identity) use($eppn) {
                         $identity->email = $_SERVER['mail'];
+                        if (isset($_SERVER['givenName'])) {
                             $identity->name = $_SERVER['givenName'];
+                        }
+                        if (isset($_SERVER['sn'])) {
                             $identity->surname = $_SERVER['sn'];
+                        }
                         $identity->eppn = $eppn;
                     });
         } else {